Wade
A few comments just looking at your dyno sheet.
1st did he weight your fuel? Because the default is .750 and renegae 112 is .711 @60 degrees F. So my 1st thought is your BSFC should be better unless the fuel was 40 degrees then it may have had a .750 SG
2nd did he tell you why he was running the Inertia correction factor at a 1.000?

Wade, I would ask him to email you a “customer data pack”. That has ALL of the data taken in by the dyno. Plus it allows you to do some post run corrections.



For those of you that don’t know what STPIPw and STPiTr are. It is corrected to STP J-607 and with inertia correction. Inertia correction is a factor added (or taken away from a decell test) the torque reading.
Why is inertia factor added? It has to do with Newtons 1st law of motion “an object either remains at rest or continues to move at a constant velocity, unless acted upon by a force”. When we do a sweep test on a Dyno, we have to accelerate the crankshaft, flywheel, drive plate, driveshaft and dyno brake. All of this takes energy and that energy can’t be measured by the brake because it being stored in all the rotating mass. Each engine has a different factor.

How do you determine the engines “Inertia factor”. You run a special sweep up and down, doesn’t have to be at full throttle. Now if you correction factor is right the HP and Tq lines will lay over each other, because we are correcting (by adding) for the energy being stored during accell and correcting (by removing) during decell. If the number is not right it can be adjusted during post analysis until it is correct.

So what have we done? Well now we can make a sweep at 200 rpm per second and 600 rpm per second and get the same HP reading. You can do a step test and get the same reading. Before a 750 rpm per second read would always have a lower HP reading than a 400 rpm reading per second run.

Joe